Britain's Queen Elizabeth II and Prince Philip privately celebrated their 65th wedding anniversary on Tuesday - a matrimonial record for a British monarch.
The queen, 86, and the Duke of Edinburgh, 91, spent the day at Buckingham Palace after attending a gala Royal Variety Performance on Monday, a spokesman said.
The Blue Sapphire anniversary, as it is known, coincides with the 60th anniversary of the queen's accession to the throne, which was celebrated earlier this year.
Princess Elizabeth, as she was then, first met Prince Philip of Greece in 1934, when both attended the wedding of Philip's cousin, Princess Marina of Greece to Princess Elizabeth's uncle, the Duke of Kent.
Princess Elizabeth and Lieutenant Philip Mountbatten, the Duke of Edinburgh, married on November 20, 1947 at Westminster Abbey, in a ceremony that provided Britain with a welcome boost amid the austerity of the immediate postwar years.
Prince Philip has been hospitalised three times recently, twice with a recurring bladder infection over the summer, and previously for a procedure to clear a blocked artery over the 2011 Christmas and New Year holiday.
An opinion poll published this week showed that, while the future of the monarchy in Britain appears secure, people are increasingly looking towards Prince William - the queen's grandson - as their future king.
Asked to name their three “most popular royals” in the Ipsos/Mori poll, 62 percent named 30-year old Prince William, followed by the queen, at 48 percent, and Prince Harry, at 36 percent.
Prince Charles, William's father and heir to the throne, ranks fifth in the popularity charts, with an approval rating of 21 percent, behind William's wife, Kate, at 23 percent. - Sapa-dpa